Ferguson called Van Persie's left-foot volley the "goal of the century".

Sir Alex Ferguson says Robin van Persie has had "as big an impact as anyone" he can remember at Manchester United after helping them win the Premier League.

The Dutchman, 29, scored a hat-trick in Monday's 3-0 win over Aston Villa that secured United's 20th league title.

He has hit 24 league goals since moving from Arsenal for £24m last summer.

Ferguson called Van Persie's left-foot volley that put United 2-0 up on the night, the "goal of the century".

The Scot added: "It was a marvellous hit, head down, over the ball, perfect timing - a magnificent strike.

"Of all the great goals we've scored over the years, from David Beckham through Ole Gunnar Solskjaer, Eric Cantona, that goal has joined that.

"He's been unbelievable. His early form in the first six months was fantastic. He had the spell where he didn't score but he was unbelievable against Villa."

Ferguson also praised some of his younger players after securing his 13th Premier League crown, and says he is confident his whole team will be even stronger next year.